標題: | Synthesis and Applications of 2,7-Carbazole-Based Conjugated Main-Chain Copolymers Containing Electron Deficient Bithiazole Units for Organic Solar Cells |
作者: | Patra, Dhananjaya Sahu, Duryodhan Padhy, Harihara Kekuda, Dhananjay Chu, Chih-Wei Lin, Hong-Cheu 材料科學與工程學系 光電工程學系 Department of Materials Science and Engineering Department of Photonics |
關鍵字: | bithiazole units;bulk heterojunction;copolymers;donor-acceptor |
公開日期: | 1-十二月-2010 |
摘要: | A series of low-band-gap (LBG) donor-accepor conjugated main-chain copolymers (P1-P4) containing planar 2,7-carbazole as electron donors and bithiazole units (4,4'-dihexyl-2,2'-bithiazole and 4,4'-dihexyl-5,5'-di(thiophen-2-yl)-2,2'-bithiazole) as electron acceptors were synthesized and studied for the applications in bulk heterojunction (BHJ) solar cells. The effects of electron deficient bithiazole units on the thermal, optical, electrochemical, and photovoltaic (PV) properties of these LBG copolymers were investigated. Absorption spectra revealed that polymers P1-P4 exhibited broad absorption bands in UV and visible regions from 300 to 600 nm with optical band gaps in the range of 1.93-1.99 eV, which overlapped with the major region of the solar emission spectrum. Moreover, carbazole-based polymers P1-P4 showed low values of the highest occupied molecular orbital (HOMO) levels, which provided good air stability and high open circuit voltages (V(oc)) in the PV applications. The BHJ PV devices were fabricated using polymers P1-P4 as electron donors and (6,6)-phenyl-C(61)-butyric acid methyl ester (PC(61)BM) or (6,6)-phenyl-C(71)-butyric acid methyl ester (PC(71)BM) as electron acceptors in different weight ratios. The PV device bearing an active layer of polymer blend P4:PC(71)BM (1:1.5 w/w) showed the best power conversion efficiency value of 1.01% with a short circuit current density (J(sc)) of 4.83 mA/cm(2), a fill factor (FF) of 35%, and V(oc) - 0.60 V under 100 mW/cm(2) of AM 1.5 white-light illumination. (C) 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 5479-5489, 2010 |
URI: | http://dx.doi.org/10.1002/pola.24356 http://hdl.handle.net/11536/26281 |
ISSN: | 0887-624X |
DOI: | 10.1002/pola.24356 |
期刊: | JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY |
Volume: | 48 |
Issue: | 23 |
起始頁: | 5479 |
結束頁: | 5489 |
顯示於類別: | 期刊論文 |